Currently available techniques and technology for providing cardiac mechanical support to a patient with heart problems and in need of cardiac resuscitation are either non-invasive and entirely external in the form of cardiopulmonary resuscitation (CPR), or highly invasive and surgical, typically in the form of an open heart gross thoracotomy (a so-called “cracked-chest” surgery).
While CPR is a well-recognized and highly effective technique for short-term emergency situations to bridge a patient back to cardiac resuscitation by the restoration of a normal sinus rhythm, it is not a technique that can be consistently and effectively used for longer periods of time or in situations involving physical damage to the patient's heart.
Most current surgical and invasive techniques and technology for cardiac resuscitation require a gross thoracotomy (usually in the form of a median sternotomy) to gain access into the patient's thoracic cavity. A surgical saw or other cutting instrument is used to dissect the sternum longitudinally, allowing two opposing halves of the anterior or ventral portion of the rib cage to be spread apart (thus, the “cracked-chest” nomenclature). A large opening into the thoracic cavity is thus created, through which the surgical team may directly visualize and operate upon the heart and other thoracic contents. Not surprisingly, a gross thoracotomy procedure involves substantial mortality risks (i.e., risk of severe immediate and eventual surgical complications, including death).
Once the gross thoracotomy is completed, a medical professional can utilize direct manual heart massage where the heart is grasped and periodically squeezes the heart in an attempt to restore blood flow. For longer term cardiac resuscitation, a left ventricular assist device (LVAD) therapy can be utilized wherein the LVAD (essentially a continuous, non-pulsatile, and externally-powered mechanical pump somewhat akin to an artificial heart) is positioned in an intracardiac location and attached in fluid communication with the heart. An LVAD typically requires an external battery pack or external vacuum port to power the LVAD for prolonged periods of time as a bridge toward ultimate cardiac transplantation.
Another less invasive surgical approach to cardiac mechanical support uses an intra-aortic balloon pump (IABP) that is inserted through the femoral artery into the descending aorta of a patient. An IABP functions to reduce afterload and improve cardiac output on a temporary basis; however, the use of an intravascular approach always increases the possibility of clots and strokes due to the presence of a mechanical device within the patient's vascular system.
Accordingly, there is a need for better solutions for providing acute cardiac resuscitation and cardiovascular mechanical support including support for select intrathoracic organs to a wide variety of patients. Such patients range from those who have incurred post-operative complications (e.g., following heart surgery) to those who have suffered traumatic injury to the thorax. Viable solution(s) that can address the shortcomings of the current techniques and technologies for providing cardiac mechanical support to patients in need of same presents an opportunity to advance the standard of care.